Specific clinical phenotypes of dry eye disease can predict the presence of matrix metalloproteinase-9 in the ocular surface

Objective: The InflammaDry test detects matrix metalloproteinase-9 (MMP-9) in tears, a biomarker associated with ocular surface inflammation. While a positive result may indicate the need for anti-inflammatory therapy, its cost and qualitative nature limit widespread use. This study aims to identify clinical phenotypes that predict positive InflammaDry results, facilitating targeted anti-inflammatory therapy without requiring MMP-9 testing. Methods: This retrospective study analyzed 1,363 patients with Dry Eye Disease (DED) from a dry eye clinic. Diagnosis was based on symptoms and at least one tear dysfunction sign. All patients underwent InflammaDry testing. Bivariate analysis (Chi-square, Student's t-test, Mann-Whitney-U) identified clinical factors associated with test positivity, which were further analyzed in a multivariable model. The proportion of InflammaDry-positive patients was compared across groups with increasing numbers of risk factors. Results: The mean age of the population was 51.4 years; 84.1 % were female, and all were Hispanic. Multivariable analysis identified several significant predictors of positive InflammaDry results: the presence of any autoimmune or allergic disease (odds ratio, OR = 1.59), corneal staining (Oxford ≥3, OR = 2.41), conjunctival staining (Oxford ≥3, OR = 2.30), low tear film viscosity (OR = 1.55), and nasal (OR 1.80) or temporal (OR = 1.47) ocular redness (Jenvis score >2 by Oculus). The frequency of a positive InflammaDry increased from 69.9 % in the total population (n = 1,363) to 100 % in those with three identified risk factors (n = 9). Conclusion: Specific systemic and ocular phenotypes can predict InflammaDry test results. Patients with specific characteristics may not require MMP-9 testing due to the high likelihood of having a positive result, potentially leading to more targeted and cost-effective management strategies.